Hygienic design energy chain in high-performance slicing plants

• What was needed: TH3 e-chains in hygienic design
• Requirements: High availability requirements with high utilisation of all components and fast, intermittent movements within the system; resistance to the cleaning agents and chemicals used in the system
• Industry: Mechanical engineering, packaging
• Success for the customer: Chain solution is easy to clean, FDA-compliant and easily withstands the chemicals used; the energy chains have been running for more than two years without any complaints; other product requirements for plain bearings, linear bearings and other semi-finished products are also supplied from a single source

The medium-sized company Dipl.-Ing. Schindler & Wagner GmbH & Co. KG develops and designs high-quality machine systems such as the high-tech slicer/check weigher machine combinations, which are used for slicing, portioning and weighing a wide variety of meat and cheese products. The high-performance slicers are characterised by the globally unique "SCHIWA walk-in design". This enables the operator to enter the interior of the machine in an upright posture and, for example, to remove the blade whilst standing when changing blades. As all surfaces have to be cleaned daily, the machines are characterised by a completely open design and easy accessibility. The new hygiene design was created for SCHIWA at the end of 2017, when the philosophy "You can only clean what you see" was applied to 'uncover' and visualise as much of the machine parts as possible.
The new machine concept influenced all the details – including the cable guidance systems to the grippers that guide the cheese to the cutting blade. Whereas previously the cables were fed through somewhere in a makeshift manner and then fixed with loops, a more suitable solution was later sought. The high performance of the machines in particular places great demands on a cable guide. The 4-lead screw slicer from SCHIWA e.g. delivers up to 6,000 cuts and 240 packs per minute with a guaranteed technical availability of 98.5%. Approximately three tonnes of cheese per hour can be processed on one machine. The system's grippers move back and forth intermittently for 20 hours a day, which places an immense load on the cable guidance. All the necessary media such as pneumatics, sensors and electrics must be safely accommodated in a guide. They were also looking for a solution made of materials that are resistant to cleaning agents and have an open design that is easy to clean.

In the search for a suitable cable guide, the company found what it was looking for at igus, with whom the machine manufacturer has had a long-standing partnership. Customised solutions made from bar stock, iglidur plain bearings and drylin linear guides are also installed in the company's own systems. "The quality, flexibility and cooperation are a perfect match, so it was clear to us from the outset that igus would be our first port of call for this energy chain," says Martin Hüttenrauch, Sales Manager at SCHIWA.
The TH3 e-chains have been in use ever since. This hygienic design e-chain is used wherever the highest hygiene requirements apply and cables and hoses need to be guided safely. It is easy to clean, FDA-compliant, has no screw connections and is ideally suited for aggressive cleaning agents and chemicals. With the up to four fixed interior segments of the e-chain, cables and hoses can be installed neatly separated from each other and still have a sufficient gap for cleaning. Another advantage of the TH3 e-chain is the rounded edges, which prevent dead spaces and the resulting formation of germs. The screw-free construction and open design also raise hygiene standards, as they make the system easier to clean.
The TH3 energy chain was first used in the 4-lead screw slicer from SCHIWA. "We have been using the energy supply systems for more than two years and we have not had any complaints so far. They are exactly what we wanted. The cables are guided safely and the blue chain is also a real eye-catcher," says Tobias Wahl, Head of Mechanical Development at SCHIWA. The choice of blue colour also follows the idea of "optical detectability", an increasingly important requirement in food technology.